2-substituted pyrazoloisoindolones as herbicides



United States Patent 3,409,425 Z-SUBSTITUTED PYRAZOLOISOINDOLONES ASHERBICIDES Euclid W. Bousquet, Wilmington, Del., assiguor to E. I. duPont de Nemours and Company, Wilmington, Del., a corporation of DelawareNo Drawing. Continuation-impart of application Ser. No. 435,351, Feb.25, 1965. This application Jan. 24, 1966. Ser. No. 522,358

6 Claims. (Cl. 7176) This application is a continuation-in-part of myapplication Ser. No. 435,351, now abandoned, filed Feb. 25, 1965.

This invention relates to pyrazoloisoindolones. More particularly, itrefers to Z-substituted pyrazoloisoindolones, compositions containingthem and their use as plant growth regulants.

Scientific endeavor approaches the plant kingdom mindful that naturalselectionhas not provided mankind with plants satisfactory for all ofmans varied needs. It is sometimes desirable to slow the growth ofplants such as lawn grasses. At the same time it is desirable to speedthe germination and development of crop plants. Frequently it isdesirable to slow bud break when spring frost threatens. At other timesa speedy bud break is necessary to shorten the growing season.

I have discovered a group of compounds that exhibit a variety ofdifferent plant growth effects. At low rates of application such effectsinclude growth retardation, epinasty, delayed flowering, prevention offruit set carbohydrate enrichment and the control of auxillary budgrowth. At higher rates of application compounds within the scope ofthis invention exhibit herbicidal action.

The compounds of my invention are described by the following formula:

i AN/N\ Rlllm I wherein R is tert-alkyl containing 4 through 12 carbonatoms,

naphthyl, phenanthryl, phthalidylalkyl where the alkyl contains 1through 3'carbon atoms or A is hydrogen, methyl, phenyl, methylphenyl orchlorophenyl; Q is hydrogen or methyl;

Preferred compounds because of their excellent activity as growthregulants are those of the formula:

wherein X can also be cyano or trifluoromethyl.

Particularly preferred because of their outstanding plant growthregulant activity are the following compounds:

3 ,3 a-dihydro-2- (p-methoxyphenyl -8H-pyrazolo [5, l-a] isoindol-8-one;

3,3a-dihydro-2- (p-chlorophenyl -8H-pyrazolo [5,1-a]

isoindol-8-one;

3,3a-dihydro-2-phenyl-8H-pyrazolo[5,1-a] isoindol-8-one.

A typical compound, .3,3a dihydro 2 (p methoxyphenyl) 8Hpyrazolo[5,1-a]isoindol 8-one, applied at rates of .01 to 1 pound peracre retards the growth of alfalfa, Black Valentine bean, soybeans,Chrysanthemum and other plants. It also inhibits the fioweringand fruitproduction of beans, soybeans and chrysanthemum. This chemical has morepronounced effects on the growth of chrysanthemum under short days,indicating that it is affecting the response of plants to day length.

On syrup type sorghum a foliar spray of M to 3 pounds per acre appliedtwo to eight weeks before harvest increases the sugar content of thesorghum.

At higher rates, such as two to four pounds per acre, this same compounddestroys goldenrod, Solidago spp.; red clover, Trifolium praetense;ragweed, Amarosia spp.; and wild carrot, Daucus carota.

Preparation The aforementioned substituted3,3a-dihydro-8H-pyrazolo[5,1-a]isoindol-8-ones are prepared in thefollowing manner. Phthalaldehydic acid or substituted acid is treated inthe presence of a base with a ketone; i.e., acetophenone or substitutedacetophenone. Generally, inert solvents such as ethanol, 2B alcohol,methanol, acetonitrile and benzene are preferred for the reaction alongwith bases such as potassium and sodium hydroxide. It is desirable tohave more than one equivalent of base.

The mixture is stirred for one to six hours at 20 to C., 25 to 35 C.being preferred. The reaction is essentially complete and is soindicated by precipitation of the compound, by disappearance of the peakattributable to the aldehyde group in the infrared spectrum or by otherappropriate means. The solution is diluted with water and acidified,usually with concentrated hydrochloric acid, which completes theprecipitation of essentially pure 3- substituted phthalide. Furtherpurification can be effected by recrystallization from an appropriatesolvent such as benzene, acetonitrile or ethanol.

A mixture of the 3-substituted phthalide and hydrazine, usually as thehydrochloride, sulfate or hydrate, in an inert solvent such as aqueousethanol or methanol is heated to near reflux. It is desirable to use anexcess of one of the reactants. After a few minutes, an excess oftriethylamine is added gradually, and the mixture is heated at refluxfor one to three hours. The cooled solution is acidified, generally withhydrochloric acid and then reheated at reflux for about thirty minutes.The solution is thereafter Compositions Compositions of this inventioncomprise a compound of this invention together with one or moresurface-active agents.

The surface-active agent used in this invention can be a wetting,dispersing or an emulsifying agent which will assist dispersion of thecompound. The surface-active agent or surfactant can include suchanionic, cationic and nonionic agents as have heretofore been generallyemployed in plant control compositions of similar type. Suitablesurface-active agents are set out, for example, in Searle US. Patent2,426,417; Todd US. Patent 2,655,447; Jones US. Patent 2,412,5 10; orLenher US. Patent 2,139,- 276. A detailed list of such agents is setforth in Detergents and Emulsifiers Annual (1965) by John W. McCutcheon,Inc.

Suitable surface-active agents for use in compositions of the presentinvention are: polyethylene glycol fatty acid esters and fatty alkylolamide condensates, alkylaryl sulfonates, fatty alcohol sulfates, dialkylesters of sodium sulfosuccinate, fatty acid esters of sodiumisethionate, polyoxyethylene ethers and thioethers and long chainquaternary ammonium chloride compounds.

Surface-active dispersing agents such as salts of lignin sulfonic acids,low viscosity methyl cellulose, polymerized sodium salts ofalkylnaphthalene sulfonic acids are also suitable in the herbicidalcompositions of this invention.

Among the more preferred surfactants are the anionic and non-ionic type.Among the anionic surface-active agents, preferred ones are alkali metalor amine salts of alkylbenzene sulfonic acids such as dodecylbenzenesulfonic acid, sodium lauryl sulfate, alkylnaphthalene sulfonates,sodium N-methyl-N-oleoyltaurate, oleic acid ester of sodium isethionate,dioctyl sodium sulfosuccinate, sodium dodecyldiphenyloxide disulfonate.Among the nonionic compounds, preferred members are alkylphenoxypoly(ethyleneoxy)ethanols such as nonylphenol adducts with ethyleneoxide; polyethylene oxide adducts to long chain aliphatic alcohols suchas trimethylnonyl polyethylene glycol ethers, polyethylene oxide adductsof fatty and rosin acids, long chain alkyl mercaptan adducts withethylene oxide, and polyethylene oxide adducts with sorbitan fatty acidesters.

In general, less than 10% by weight of the surfaceactive agents will beused in compositions of this invention and ordinarily the amount ofsurface-active agents will range from 15% but may even be less than 1%by weight.

Additional surface-active agents can be added to the above formulationto increase the ratio of surface-active agentzactive agent up to as highas 5:1 by weight. Normally the purpose of adding higher amounts ofsurfactant is to increase the growth regulant effect of the activecompounds. When used at higher rates it is preferred that the surfactantbe present in the range of one fifth to five par ts surfactant for eachone part of active agent.

Plant growth regulant compositions of this invention can contain, inaddition to a surfactant, finely divided inert diluents such as talcs,natural clays including attapulgite clay and kaolinite clay,pyrophyllite, diatomaceous earths, synthetic fine silicas, calciumsilicate, carbonates, calcium phosphates, sulfur, lime and such floursas walnut shell, wheat, redwood, soybean and cottonseed.

Preferred diluents are clays of hydrated aluminum silicate, hydratedaluminum magnesium silicate and hydrated aluminum magnesium ironsilicate.

The amount of the finely divided inert solid diluent can vary widely butwill-generally range from to 98% by weight of the growth retardantcomposition, The particle size can vary considerably but will ordinarilybe somewhat under microns in the finished formulation. Such compositionsare prepared by blending the ingredients and grinding in a hammer millor an air attrition mill or similar device until uniform powders areobtained which have a particle size smaller than 50 microns.Compositions containing a surface-active agent and a solid inert diluentare preferably wettable powders containing from 25 to 90% of apyrazoloisoindolone.

The pyrazoloisoindolones of this invention can also be formulated ashigh strength compositions in which the active ingredient can be presentin amounts ranging from 9099%. The remainder of the compositioncomprises surface-active agents, preferably in amounts of from 0.2 to 2%and diluents, as described above. Such compositions are prepared byblending and grinding the ingredients to obtain a homogeneous powder offine particle size.

Compositions of these plant growth regulants and inert solid diluentscan also be formulated into granules and pellets. In such compositions,the diluent will generally range from 65 to 99% and the activeingredient can range from 1 to 35%. It should be understood that it willnot be necessary to include a surfactant in the granular and pelletizedcomposition. To prepare granules the pyrazoloisoindolone can bedissolved in a solvent, and this solution can be sprayed over pre-formedclay granules, expanded vermiculite or the like while agitating themixture to distribute the active ingredient over and throughout thegranular mass. Such granules can range in particle size of from mesh to+4 mesh, and an active ingredient content of 1 to 6% is preferred. It isalso possible to make such granules by mixing the finely divided diluentand finely divided pyrazoloisoindolone, for instance by grindingtogether, and then forming granules by adding water, tumbling and dryingthe resulting spheres. It is also possible to mix a finely dividedpyrazoloisoindolone with granular carriers such as attapulgite orvermiculite and then binding the active ingredient to the carrier byspraying the whole with a non-volatile liquid.

Pellets can be prepared by extruding a mixture which comprises thepyrazoloisoindolone, pelleting clay diluent and water into strands,cutting these, and drying the product. Pellet size can range from 10mesh to larger shapes such as /8 inch cubes. Pellets preferably containfrom 5 to 35% of the pyrazoloisoindolone. In addition to the diluents,pelletized and granular compositions can contain additives such asbinders, surfactants and the like.

In addition to the formulation described above, suspension concentratescan also be prepared. These formulations are prepared by wet milling theingredients; i.e., ball milling or by sand grinding using the methoddescribed in Hochberg US. Patent 2,581,414, issued Aug. 19, 1948 orLittler US. Patent 3,060,084, issued Oct. 23, 1962. Using the methodsdescribed in these patents, fine particles of the active compoundswithin the scope of this invention will be dispersed evenly in adiluent. Such compositons normally contain from 15 to 50% activeingredient and are characterized by having particles which aresubstantially less than 5-20 microns in diameter.

Water extendable oil compositions can also be employed with one or moreof the pyrazoloisoindolones of this invention. In these plant growthregulant compositions, surface-active agents and an oil form a liquidwhich can be conveniently poured and measured. Such liquid concentratescan be mixed with water at the point of application to form a dilutespray containing the herbicide and the surface-active agent. Suchcompositions have the advantage that the oil will often act as a foaminhibitor and thus reduce the tendency for large amounts of surfactantsto form objectionable foam. These oil formulations are dispersions ofthe pyrazoloisoindolones in finely divided form in non-solvent carriers.A non-solvent carrier is an oil in which the pyrazoloisoindolone has lowsolubility, for instance, less than about 0.1% at C. Many aliphatichydrocarbons are examples of such nonsolvent carriers. The dispersionsare prepared by wetmilling the ingredients, for example, in a ball millor sand 5 mill. The solutions are prepared by blending and agitating theingredients, possibly with application of heat.

In these emulsifiable oil concentrates, the pyrazoloisoindolones will bepresent in amounts ranging from 5 to by weight. Precise concentrationsof active agent, of course, will depend on the intended use of thecomposition. Upon mixing with water at the point of application, the oilconcentrate will be diluted so that in the final formulation the activeagent will be present in amounts ranging from 0.5% to 2% by weight. Itwill 15 be understood that emulsifiable compositons will have utilityfor regulating foliage along highway and railroad rights-of-way, as wellas other locations.

It is, of course, also possible to use such oil compositions ofpyrazoloisoindolones by extending them with other oils, for example,diesel oil, herbicidal oil, and the like for applications such asrailroad rights-of-way.

Formulation with herbicides The pyrazoloisoindolones of my invention canbe formulated with other classes of compounds, producing compositionshaving advantages over the individual components. Among the known plantgrowth retardants, modifiers and herbicides which can be combined withthe pyrazoloisoindolones of this invention are: 30

Substituted ureas 3- 3 ,4-dichlorophenyl)-1,1-dimethylurea3-(4-chlorophenyl)-1,1-dimethylurea 3-phenyl-1,1-dimethylurea3-(3,4-dichlorophenyl)-3-methoxy-1,1-dimethylurea 3- (4-ch1orophenyl-3-methoxy- 1 l-dimethylurea 3- 3,4-dichlorophenyl)l-n-butyll-methylurea 3- (3,4-dichlorophenyl) -1-methoxy-1-methylurea3-(4-chloropheny1) l-methoxyl-methylurea3-(3,4-dichlorophenyl)-1,1,3-trimethylurea 3- (3,4-dichlorophenyl)-1,1-diethylurea These ureas can be mixed with thepyrazoloisoindolones of this invention in proportions of from 1:4 to16:1 respectively, the preferred ratio being 1:4 to 8: 1.

1-(2-methylcyclohexyl)-3-phenylurea 1- 3-methylcyclohexyl -3phenylureaThe above two ureas can be mixed with the pyrazoloisoindolones of thisinvention in proportions of from 1:4 to 40: 1.

Substituted triazines These triazines can be mixed with thepyrazoloisoindolones of this invention in proportions of from 1:4 to16:1

respectively, the preferred ratio being 1:4 to 8:1. 7

6 Phenols 4-cyano-2,6-diiodophenol and its salts4-cyano-2,6-dibromophenol and its salts dinitro-o-sec-butylphenol andits salts pentachlorophenol and its salts These phenols can be mixedwith the pyrazoloisoindolones of this invention in the proportions of1:4 to 20:1 respectively, the preferred ratio being 1:4 to 10: 1.

Carboxylic acids and derivatives The above carboxylic acids can be mixedwith the pyrazoloisoindolones of this invention in the proportion of 1:8to 8: 1, preferably a 1:4 to 4:1 ratio.

2,6-dichlorobenzonitrile Mixed in a 1:8 to 8:1 ratio, preferably a 1:4to 4:1 ratio.

Trichloroacetic acid and its salts Mixed in a 1:2 to 40:1 ratio,preferably a 1:1 to 8:1 ratio.

2,2-dichloropropionic acid and its salts Mixed in a 1:2 to 8:1 ratio,preferably a 1:2 to 6:1 ratio.

N,N-dipropylthiolcarbamic acid, ethyl estern-Propyl-N,N-dipropylthiolcarbamateN-propyl-N-ethyl-n-butylthiolcarbamate Mixed in a 1:2 to 8:1 ratio,preferably a 1:1 to 4:1 ratio.

N-phenylcarbamic acid, isopropyl ester N-(m-chlorophenyDcarbamic acid,isopropyl ester N-(m-chlorophenyl)carbamic acid, 4-chloro-2-butynylester Mixed in a 1:2 to 8:1 ratio, preferably a 1:1 to 4:1 ratio.2,3,6-trichlorophenylacetic acid and its salts Mixed in a 1:8 to 8:1ratio, preferably a 1:4 to 4:1 ratio.

N -isopropyl-N-phenylchloroacetamide 2-chloro-N,N-diallylacetamideMaleic hydrazide Succinic acid, monohydrazide with hydrazine 1,l-dimethyl-(2-chloroethyl)trimethylammonium chloride Tributyl2,4-dichlorobenzylphosphorium chloride(4-hydroxycarvacryl)trimethylammonium chloride, ester withl-piperidinecarboxylic acid Mixed in a 1:4 to 16:1 ratio, preferably a1:2 to 8:1 ratio.

Inorganic and mixed inorganic-organic salts These salts can be mixedwith the pyrazoloisoindolones of this invention in the below listedproportions.

7 Calcium propylarsonate Disodium monomethylarsonateOctyl-dodecylammoniummethylarsonate Mixed in a 1:4 to 16:1 ratio,preferably a 1:2 to 4:1 ratio.

Sodium arsenite Sodium chlorate Mixed in a 2:1 to 200:1 ratio,preferably a 1:1 to 100:1 ratio.

Ammonium sulfamate Mixed in a 1:1 to 100:1 ratio, preferably a 1:1 to50:1 ratio.

Other organic herbicides 5,6-dihydro-(4A-6A)-dipyrid0-(1,2-A,2,1'-C)pyrazinium dibromide 1,1-dimethyl-4,4'-dipyridinium di-(methylsulfate)Mixed in a 1:10 to 8:1 ratio, preferably a 1:5 to :1 ratio.3-amino-l,2,4-triazole Mixed in a 1:10 to 10:1 ratio, preferably a 1:5to 5:1 ratio. 3,6-endooxohexahydrophthalic acid Mixed in a 1:3 to 20:1ratio, preferably a 1:2 to 10:1 ratio.

Hexachloroacetone Mixed in a 1:2 to 32:1 ratio, preferably a 1:1 to 16:1ratio.

Diphenylacetonitrile N,N-dimethyl-alpha,alpha-diphenylacetamideN,N-di-n-propyl-2,6-dinitro-4-trifluoromethylanilineN,N-di-n-propyl-2,6-dinitro-4-methylanilineN-methyl-N-n-butyl-2,6-dinitro-4-butyromethylaniline Mixed in a 1:2 to30:1 ratio, preferably a 1:1 to 8:1 ratio.

O-(2,4-dichlorophenyl)-O-methyl-isopropylphosphoramidothiate2,3,5,6-tetrach1oroterephthalic acid, dimethyl ester Thio-methyl esterof 2,3,5,6-tetrachloro-4-carbomethoxybenzoic acid Mixed in a 1:2 to 30:1ratio, preferably a 1:3 to :1 ratio.

1-(3,4-dichlorophenyl)-3,S-dimethylhexahydro-1,3,5-

triazinone-Z 1-phenyl-3-methyl-5-allyl hexahydro-1,3,5-triazinone-2Mixed in a 1:4 to 16:1 ratio, preferably a 1:4 to 8:1 ratio.

Substituted uracils These pyrazoloisoindolones can be mixed withsubstituted uracils, in the proportions listed below.

3-cyclohexyl-6-methyluracil 3-cyclohexyl-6-ethyluracil3-norbornyl-6-methyluracil 3-cyclopentyl-6-methyluracil3-isopropyl-S,G-pcntamethyleneuracil Mixed in a 1:4 to 16:1 ratio,preferably a 1:2 to 8:1 ratio.

3-cyclohexyl-5,6-t1imethyleneuracil 3-sec-butyl-5 ,6-trimethyleneuracil3-isopropyl-5,G-trimethyleneuracil 3-isopropyl-5,6-tetramethyleneuracil3-isopropyl-5,6-pentamethyleneuracil Mixed in a 1:4 to 16:1 ratio,preferably a 1:4 to 8:1 ratio.

3-cyclohexyl5-bromouracil 3-cyclohexyl-5-chlorouracil3-isopropyl-5-bromouracil 3-sec-butyl-5-bromouracil3-sec-butyl-S-chlorouracil 5-bromo-3-sec-butyl-6-rnethyluracil5-bromo-3-sec-butyl-6-methyluracil, sodium salt 5-chloro-3-sec-butyl-6-methyluracil 5-bromo-3-tert-butyl-6-methyluracil5-chloro-3-tert-butyl-6-methyluracil 5-bromo-3-( l-ethylpropyl)-6-methyluracil 5-chloro-3-( l-ethylpropyl -6-methyluracil5-bromo-3-isopropy1-6-methyluracil 5-chloro-3 -isopropyl-6-methyluracil5-bromo-3-cyclohexylmethyl-6-methyluracil5-chloro-3-cyclohexylmethyl-6-methyluracil3-cycloheXyl-5-methoxy-6-methyluracil 3-sec-butyl-S,6-dimethyluracil5-bromo-6-methyl-3 -norbornylmethyluracil3-sec-butyl-6-methyl-5-nitrouracil 3-cyclohexyl-5,6-dimethyluracil 5-bromo-3-cyclohexyl-6-methyluracil 5-chloro-3-phenyl-6-methyluracil5-bromo-6-methyl-3-( 1-piperidino uracil 5 -chloro-6-methyl-3-(l-piperidino uracil 5-bromo-6-methyl-3-( l-pyrrolidinyl)uracil5-chlor0-6-methyl-3 l-pyrrolidinyl uracil 5-bromo-6-methyl-3-(hexahydro- 1 -azepinyl uracil 5-chloro-6-rnethyl-3-(hexahydrol-azepinyl) uracil 6-methyl-3-(hexahydro-1-azepinyl) uracil5bromo-6-methyl-3- (4-morpho1ino uracil Mixed in a 1:2 to 8:1 ratio,preferably a 1:1 to 4:1 ratio.

3-isopropyl-1-trichloromethylthio-5-bromo-6-methyluracil3-cyclohexyl-1-trichloromethylthio-5-bromo-6-methyluracil3-sec-butyll-acetyl-S-bromo-o-methyluracil 3-isopropyl-1-acetyl-5-bromo-6-methyluracil3-isopropyl-1-trichloromethylthio-5-ch1oro-6-methyluracil Mixed in a 1:4to 16:1 ratio, preferably a 1:4 to 3:1 ratio.

Application The compounds of my invention are applied to the locus ofgrowth of the plants to be affected. A locus of growth is meant theimmediate area where the plant is developing and growing. This includespre-emergence and post-emergence application.

Low rates of application of the active ingredient from 0.0025 to 8pounds per acre provides a means for regulating the growth of plants;e.g., growth retardation which includes epinasty, delayed flowering,preventing of fruit set carbohydrate enrichment and control of axillarygrowth. At higher rates of application, from 10 to 40 pounds per acre,compounds of this invention exhibit herbicidal activity on some plantspecies under specific 9 growth conditions. However, on other plantspecies these Percent compounds are herbicidal at a rate of two poundsper 3,3a-dihydro 2 (p-methoxyphenyl)-8H-pyrazoloacre or even lower. Thecompound is applied with con- [5,1-a]isoindol-8-one 80.0 ventionalagricultural equipment and is usually applied Alkylnaphthalene sulfonicacid, Na salt 1.5 in one of the compositions set forth above. The actual5 Partially desulfonated sodium lignin sulfonate 2.0 rate of activeingredient used, of course, must depend Synthetic fine silica 16.5

on the particular situation, i.e., the actual plant species, its vigor,the time of year and the condition of the soil. These slight variationswill be well known to one skilled in the art.

The following examples are provided to more clearly explain thisinvention. All percents are by weight unless an aqueous spray otherwlsemdlcated' Five pounds of this wettable powder is mixed with a EXAMPLE 1PREPARATI()N OF 3,3a-DII-IYDRO- small quantity of water and a slurryformed. The slurry 2-(p METHOXYPHENYL)-8H-PYRAZOLO[5,1-a] is thendiluted to 100 gallons with water and 0.2% of ISOINDOL-S-ONE dodecylether of polyethylene glycol is added.

This suspension is sprayed on recently trimmed trees and brush,including privet and Lombardy poplar and sumac along a power lineright-of-way. The application is made when the trees are in leaf and thefoliage is sprayed to run-off. This treatment greatly retards the growthof the trimmed species. The labor required to maintain the power lineright-of-way is reduced.

The above components are first mixed in a ribbon blender, thenmicropulverized until substantially all par- 10 ticles are belowmicrons, and reblended to yield a readily dispersible wettable powderfor application as To 237 parts of ethanol containing parts by weight of4-methoxyacetophenone and 75 parts of phthalaldehydic' acid is addedgradually 56 parts of potassium 2O hydroxide in 50 parts of water. Themixture is stirred for a period of about one hour The solution isdiluted with water and acidified with concentrated hydrochloric acid togive.103 parts of essentially pure 3-(p-methoxyphenacyl)phtl1alide. Amixture of 141 parts by weight of 25 3-(p-methoxyphenacyl)phthalide andparts of hy drazine hydrochloride in 914 parts of 60% aqueous I ethanolis heated to near reflux. After a few minutes, 202 The fellewmgcompounds are made llke manner as parts of triethylarnine is addedgradually, and the mixthe 2 (P -P q ture is heated at reflux for aperiod of three hours. The 30 :1 ahsomdel 8 one of Example 1 ySubstltutlng cooled solution is acidified with concentrated hydr0equlvalent amounts of the ketone and substituted phthalchloric acid andthen reheated. at reflux for about onelde below for the Y 9P and (P'half hour. After the mixture is cooled, concentrated andmethoxyphenaeyl)Phthallde l'espeetlvely of Example diluted with about500 parts of water, essentially pure T Phthalaldehydle ae1d reactant ofExample 1 15 used 33a dihydro 2 (IHnethOXYPhenyI) 8H 1 5 1 35 in each ofthe following preparations except when isoindopgone Separates; p 177 1735 1 A specifically substituted phthaldehydic acids are listed asEXAMPLES 2179 sorption 5.88 1; proton n.m.r. consistent with structure.ill Examples All the compounds are formulated Analysis.-Calcd for C H NO C, 73.38; H, 5.04; and applied in like manner to provide plant growthre- N, 10.07. Found: C, 73.23; H, 5.10; N, 9.89. tardation.

Ex. Ketone Substituted Phthalide Substituted Pyraz01o[5,1-a]is0indolones2 l-acetylnaphthalene 3-[2-(l-naphthyl)-2-ox0ethy1]phthalide 3,g -dhydT0-2-(l-naphthyl)-8H-pyraz0l0[5,1-a]isoindol- -0I16. 32'acetylnaphthalene 3-[2-(2-napl1thy1)-2-oxoethyl]phthalide.. 3, 8' -dhyd 0- -(2-naphthyl)-8H-pyraz0lo[5,1-a]isoindo1 One. 4Q-acetylphenanthrene 3-[2-oxo-2-(9-phenanthryl)ethyl]phthalide.. 3,3a-dilyiigp-2-(9-phenanthryl)-8H-pyrazo1o[5,1-a]

180111 0- 0116. 5 3,3-dimethy1-2-butanone3-(3,3-dimethyl-2-oxobutyl)phthalide....-2-gert-buty1-3,3a-dihydro-8H-pyrazolo[5,1-a]isoindo1- '0116. 63-buten-2-one 3-(3-butenyl-2-oxo)phthalide3,3a-dihydro-2-viny1-8H-pyrazo1 -[5,1- ].i m 1.3. 74-Inethyl-3-penten-2-one 3-(4-methyl-2-oxo-3-pentenyl)phthalide.-..3,?2- 11Iiy g-g thyl-l-propenyl)-8H-pyrazo1o -31S0111 0 -O118. 83-penten-2-one 3-(2-oxo-3-penteny1)phthalide3,3ga-dihydm-2-(l-propenyl)-8H-pyrazolo[5,1-a]isoindo1- one.4-phenyl-3-buten-2-one 3-(2-oxo4-phenyl-3-butenyl)phthalide-.. 3,3a-dihyI0-2-Styry1-8H-pyi'azo1o[5,1-a1-isoindo1-g-0ne. 4-p-tolyl-3-buten-2-one3-(2-oxo-4-p-toly1-3-butenyl)phthalide3,3a-d1hydr0-2-(p-methylstyry1)-8H-pyrazolo[5,l-a]

isoindol-B-one. 3-(2-oxo-4-m-tolyl-3-butenyl)phthalide3,3a-dihydro-2-(m-methylstyryl)-8H-pyrazolo[5,1-a]' isoindol-8-one 114-m-t0ly1-3-buten-2-one 12 4-1)-ehlorophenyl-3-buten-2-one3-(4-p-ehl0r0phenyl-2-oxo-3-butenyl)2-(p-chlorostyryl)353a-dihydro-8H-pyrazolo[5,1-a]

phthal' e. isomd -8-0ne. j 13 4-m-ch1orophenyl-3-buten-2-one3-(4-m-chloropheny1-2-oxo-3-buteny1) 2-(inchIorostyryl)-3,3a-d1hydro-8H-pyrazolo[5,1-a]

phthalide. isoindol-8-one. 14 2-chloroacetophenone3-(o-chlorophenacyl)phthalide2-g0-ehliolioghenY1)3,3a-d1hydro-8H-pyrazolo[5,1-a]

isoin o -one. 15 3-chloroacetophenone 3-(m-chlorophenacyl)phthalide 2-gmcllofgphenyl)-3,3a-dihydro-8Hpyrazolo[5,l-a]

isom o -one. 16 4'-chloroaeetophenone 3-(p-chlorophenacyl)phthalide 2-(pclgo{%phenyl)-3,3a-dihydro-8H-pyrazolo[5,1-a]

150111 0 -one. 17 2-fluoroacetophenone 3-(o-fiuorophenacyl)phthalide2-go-tlugringhenyl)-3,3a-dihydro-8H-pyrazo1o[5,1-a]

180111 0 -one. 18 3fiuoroacetophenone B-(m-fluorophenacyl)phthalide 2-tmflgoftgphenyl)-3,3a-dihydro-8H-pyrazolo[5,1-a]

. 150111 0 -one. 4-fluoroaeetophenone 3-(p-fluorophenaeyl)phthalide2-gp-ghgirfighenyl)-3,3a-dihydro-8H-pyrazolo[5,1-a]

ison 0 one. 20 2-bromoacetophenone. 3-(o-bromophenacyl)phthalide2-go-brgnitgphenyl)-3,3a-dihydro-8H-pyrazolo[5,1-a]

[S0111 O -one. 21 3-bromoacetophenone 3-(m-bromophenaeyl)phthalide 2-gmbaolf iphenyl)-3,3a-dihydro-8H-pyrazolo[5.1-a]

isom 0 -one. 22 4-bromoacetophenone 3-(p-bromophenacyl)phthalide.-...2-p-brgni%phenyl)-3,3a-dihydro-8H-pyrazo1o[5,1-a]

soin o -one. 23 4-iodoacetophenone 3-(p-iodophenacyl)phthalide2-(p-iodophenyl)-3,3a-dihydro-8H-pyrazolo[5,1-a1isoindo1- sFone. 242-methylacetophenone 3-(o-methylphenacyhphthalide3,3a-dihydro-2-(o-tolyl)-8H-pyrazolo[5,1-a]isoindo1-8 one. 253'-methylacetophenone 3-(m-methylphenacy1)phthalide3,3a-dihydro-2-(In-tolyD-SH-pyrazolo[5,1-a11soindol-8-one. 264-methylacetophenone 3-(p-methylphenacyl)phthalide...3,3a-dihydro-2-(p-tolyl)-8H-pyrazolo[5,1-a]isoindol-8-one. 274-ethy1acetophenone 3-(p-ethy1phenacyl)phthalide2-(p-etlylrhenyl)-3,3a-dihydro-8H-pyrazolo[5,1-a]

180111 0 -one.

28 4-isopropylacetophenone 3-(p-isopropylphenacyl)phthalide2-(8p-cumyl)-3,3a-dihydro-8H-pyrazolo[5,1-a1isoindol- -one.

17 to give 55 parts of essentially pure 3-(p-fluorophenacyl)- phthalide.

A mixture of 22 parts by weight of 3-(p-fiuorophenacyl)-phthalide and 17parts of hydrazine hydrochloride in 500 parts of 2B alcohol and 100parts of water is heated to near reflux. After a few minutes, 32 partsof triethylamine is added gradually and the mixture is heated at refluxfor a period of 3 hours. The cooled solution is acidified withconcentrated hydrochloric acid, and then reheated at reflux for A2 hour.The solution is cooled, reduced in volume and diluted with about 600parts of water to give 116 parts of essentially pure Z-(p-ffuorophenyl)3,3a dihydro 8H-pyrazolo[5,1-a]isoindol-8- one.

The pure compound is formulated as-follows:

Percent 3,3-dihydro-2- p-fluorophenyl) -8H-pyrazolo [5 l-a] The abovecomponents are blended and micropulverized as in Example 1. I

One-half pound of this formulation is suspended in 60 gallons of water.This suspension is applied to greenhouse chrysanthemums by spraying thefoliage to the point of run-off. This application is made in the latesummer while the plants are still in the vegetative state.

This treatment prevents the floral induction of plants for approximatelythree months during the short days of fall and winter, eliminating theneed for supplemental light to keep the plants vegetative until flowersare desired. By varying the dosage rate of the treatment, one is able tohave chrysanthemums plants in flower at any time during the Winter orspring without the use of supplemental lighting.

EXAMPLE 182 Percent 3,3 a-dihydro-2-phenyl-8H-pyrazolo[5,1-a]isoindol-8-one 25.0 Sodium lauryl sulfate 0.5 Ca, Mg lignin sulfonate 1.0 Kaolinclay 73.5

The above components are blended and ground in the manner of theformulation of Example 1.

A suspension of 2 to 4 pounds of active ingredient of this formulationin 60- gallons of water is prepared. This suspension is sprayeduniformly over an acre of bluegrass turf.

The treatment retards the growth of the grass over an extended period,reducing the mowing necessary to maintain the area. The treatmentpromotes axillary bud development on the treated plants making the turfthicker. At the same time, good control of buckhorn plantain, wildcarrot, and aster is noted.

An application of pound of active ingredient in 60 gallons of watergives a 90% reduction in flowering and fruit production on BlackValentine bean. The bean plants exhibit an 80% growth reduction.

EXAMPLE 183 1 Percent 3,3a-dihydro-2-phenyl-8H-pyrazolo[5,l-a]-isoindol-8-one 25.0 Alkylnaphthalene sulfonic acid, Na salt 1.0Anhydrous sodium sulfate a 15.0

Non-swelling Ca, Mg bentonite 30.0 Kaolin clay 29.0

lengths as they extrude to form pellets which are then dried.

18 These pellets are used as a soil application to retard the growth ofbush species.

EXAMPLE 184 Percent 3,3a-dihydro-2- (p-methoxyphenyl) -8H-pyrazolo-[5,1-a]isoindol-8-one 35.0 Ca, Mg lignin sulfonate 15.0 Hydratedattapulgite 1.5 Sodium pentachlorophenate 0.7 Sodium hydroxide 0.6 Water47.2

The active component is first micropulverized then combined with theother components and the slurry ground in a sand mill untilsubstantially all particles are smaller then 5 microns.

This formulation is mixed with water at the rate of five pounds ofactive ingredient per gallons of water and four pounds ofpolyoxyethylene sorbitan monolaurate are added. This suspension issprayed to run-off on roadside vegetation containing a mixture ofgrasses and herbaceous annuals and perennials.

The treatment retards the growth of vegetation along the roadside andreduces the number of mowings necessary to maintain a neat roadright-of-way. The treatment also prevents the flowering and seed set onmany of the plants present, thereby reducing the seed present topropagate undesirable annual weedy grasses and broadleaves.

EXAMPLE 185 Percent 3,3a dihydro 2 (p-chlorophenyl)-8H-pyrazolo-[5,1-a]isoindol-8-one 5.00 Fine silica 1.25 Granular vermiculite 88.75Trimethylnonyl polyethylene glycol ether 5.00

The active component and fine silica are first blended andmicropulverized, then blended gently with the granular vermiculite. Thesurfactant is mixed with an equal weight of water and sprayed upon themixture previously prepared. The water is final product.

A spreader is used to apply this granular product to a lawn at the rateof 2 pounds of formulation per 1000 square feet. The application is madewhen the grass is wet from dew or the area to be treated is wet with alawn sprinkler just prior to treatment.

The treatment retards the growth of a bluegrass lawn, greatly reducingthe number of mowings necessary to maintain it in an attractivecondition. The chemical treatment also promotes axillary growth on thetreated lawn, making the turf thicker.

EXAMPLE 186 One half to one pound of3,3a-dihydro-2-(p-methoxyphenyl)8H-pyraZo10[5,1-a]isoindo1- 8-one andtwo to four pounds of maleic hydrazide are dispersed in 100 gallons ofwater. This mixture is applied to run-off as a foliar spray to trimmedtrees with about four inches of regrowth, along a power lineright-of-way.

This treatment curtails the growth of the trimmed trees. The treesrequire less frequent trimming to keep them below the transmissionlines.

EXAMPLE 187 One pound of3,3a-dihydro-2-(p-chlorophenyl)-8H-pyrazolo[5,1-a]isoindol-8-one andeight pounds of 2,3,5,6 tetrachloroterphthalic acid, dimethyl ester aresuspended in 50 gallons of water.-This mixture is sprayed in earlyspring on an acre of mixed turf grasses and broadleaved weeds in a lawnaround a manufacturing plant.

The treatment effectively removes broadleaf weeds such as buckhornplantain, Plantago lanceolata; daisy fieabane, Erigeron spp. andbroadleaf plantain, Plantago major permitted to evaporate to give thefrom the turf and controls crabgrass, Digitaria spp. The treated turfhas a much more pleasing appearance than surrounding untreated areas. Atthe same time the treatment significantly reduces the number of requiredmowings during the season.

.EXAMPLE 188 Three-fourths to three pounds of 3,3a-dihydro-2-(3,4,5-trimethoxyphenyl) 8H pyrazolo[5,1 a]isoindol-8-one, formulated as awettable powder, is suspended in 40 gallons of water. This suspensionis'applied to an acre of rice as a pre-emergence or early post-emergencespray. I

This treatment effectively controls barnyard grass, Echinochloacrusgalli, up to three inches tall at the time of treatment. It alsocontrols this weed when applied preemergence.

EXAMPLE 189 Two and eight-tenths pounds of the formulation of Example184 is suspended in a sufficient amount of water to provide a totalvolume of six gallons. A non-phytotoxic wetting agent such aspolyoxyethylene sorbitan monolaurate (0.15 pounds) is added. Theresulting suspension is sprayed over an acre of sugarcane about sixweeks before harvest.

The treated plants do not flower before harvest while sugarcane in anadjacent field develop flowers.

EXAMPLE 190 Percent 3,3a dihydro Z-(p-methoxyphenyl)-8H-pyrazolo-[5,1-a1isoindol-8-one 80 Alkylnaphthalene sulfonic acid, Na saltPartially desulfonated sodium lignin sulfonate Synthetic fine silicaEXAMPLE 19 1 Three ounces of the formulation of Example 191 is suspendedin 104 gallons of water and one pound of a nonphytotoxic wetting agentsuch as polyoxyethylene sorbitan monolaurate is added. The resultingsuspension is sprayed over an acre of syrup type sorghum about eightweeks old. The plants are 36 to 42 inches tall at this time but seedhead development is not apparent.

The treatment prevents flowering and subsequent grain development. Afterthe sorghum is harvested and compared with an acre of untreated sorghumit is noticed that a significantly greater yield of syrup is obtainedfrom the treated sorghum.

The invention claimed is:

1. A plant growth retarding composition comprising a major amount of aninert diluent and a plant growth retarding amount of a compound of theformula:

wherein R is selected from the group consisting of tert-alkyl of 4through 12 carbon atoms,

, naphthyl, phenanthryl, phthalidylalkyl where the alkyl is 1 through 3carbon atoms and m is 1 when R is fluorine and is a whole number lessthan 5 when R is selected from the group consisting of chlorine andbromine;

A is selected from the group consisting of hydrogen,

methyl, phenyl, methylphenyl, and chlorophenyl;

Q is selected from the group consisting of hydrogen and methyl;

X is selected from the group consisting of hydrogen, halogen, alkyl of 1through 4 carbon atoms, alkoxy of 1 through 4 carbon atoms, alkylthio of1 through 4 carbon atoms, nitro, methylsulfonyl, trifluoromethyl andcyano;

Y and Z are each separately selected from the group consisting ofhydrogen, halogen, alkyl containing 1 through 4 carbon atoms, and alkoxycontaining 1 through 4 carbon atoms;

R" is selected from the group consisting of hydrogen, alkyl of 1 through4 carbon atoms and cyano; and R' is selected from the group consistingof hydrogen,

fluorine, chlorine and bromine.

2. Method for retarding the growth of plants comprisin-g applying to thelocus of growth of a plant, a growth retarding amount of a compound ofthe formula:

I AT/ wherein R is selected from the group consisting of tert-alkyl of 4through 12 carbon atoms,

m is 1 when R is fluorine and is a whole number less than 5 when R' isselected from the group consisting of chlorine and bromine;

A is selected from the group consisting of hydrogen,

methyl, phenyl, methylphenyl, and chlorophenyl;

Q is selected from the group consisting of hydrogen and methyl;

X is selected from the group consisting of hydrogen, halogen, alkyl of 1through 4 carbon atoms, alkoxy of l'through 4 carbon atoms, alkylthio of1 through 4 carbon atoms, nitro, methylsulfonyl, trifluoromethyl andcyano;

Y and' Z are each separately selected from the group consisting ofhydrogen, halogen, alkyl containing 1 through 4 carbon atoms, and alkoxycontaining 1 through 4 carbon atoms;

R is selected from the group consisting of hydrogen, alkyl of 1 through4 carbon atoms and cyano; and R is selected from the group consisting ofhydrogen,

fluorine, chlorine and bromine.

3. Method accordingto claim 2 wherein the compound applied is3,3a-dihydro-2-(p-methoxyphenyl)-8H- pyrazolo[5,l-a] isoindol-S-one.

4. Method according to claim 2 wherein the compound applied is3,3a-dihydro-2-(p-chlorophenyl)-8H- pyrazolo [5, 1-a]isoindol-8-one.

5. Method according to claim 2 wherein the compound applied is3,3a-dihydro-Z-phenyl-8H-pyrazolo [5,1-a]isoindol-8-one.

6. Method of controlling the growth of plants comprising applying to alocus to be protected 21 herbicidal amount of a compound of the formula:

wherein R is selected from the group consisting of tert-alkyl of 4through 12 carbon atoms,

oli-A naphthyl, phenanthryl, phthalidylalkyl where the alkyl is 1through 3 carbon atoms and m is 1 when R' is fluorine and is a wholenumber less than 5 when R is selected from the group consisting ofchlorine and bromine;

A is selected from the group consisting of hydrogen,

methyl, phenyl, methylphenyl, and chlorophenyl;

Q is selected from the group consisting of hydrogen and methyl;

X is selected from the group consisting of hydrogen, halogen, alkyl of 1through 4 carbon atoms, alkoxy of 1 through 4 carbon atoms, alkylthio of1 through 4 carbon atoms, nitro, methylsulfonyl, trifluoromethyl andcyano;

Y and Z are each separately selected from the group consisting ofhydrogen, halogen, alkyl containing 1 through 4 carbon atoms, and alkoxycontaining 1 through 4 carbon atoms;

R" is selected from the group consisting of hydrogen, alkyl of I through4 carbon atoms and cyano; and R is selected :from the group consistingof hydrogen,

fluorine, chlorine and bromine.

References Cited UNITED STATES PATENTS 12/1942 Avery 71-25 l/ 1946Barnhill 712.5

30 LEWIS GOTIS, Primary Examiner.

G. HOLLRAH. Assistant Examiner.

1. A PLANT GROWTH RETARDING COMPOSITION COMPRISING A MAJOR AMOUNT OF ANINERT DILUENT AND A PLANT GROWTH RETADING AMOUNT OF A COMPOUND OF THEFORMULA: